Add ability to use tags as global filter for dashboards

[NishantSingh-DH]

Problem Statement

Our web application has microfrontend architecture. We want to create a general dashboard for our microfrontends where one can select a microfrontend from global filter and can see all widget values corresponding to its microfrontend.
Similarly, we want to have other global filters like country, brand which can be in form of multiselect or single select.

Solution Brainstorm

Introduces custom filters in dashboard which can be applied globally and have capabilities to be either multi select or single select.

Product Area

Dashboards

┆Issue is synchronized with this Jira Improvement by Unito

[getsantry]

Assigning to @getsentry/support for routing ⏲️

[getsantry]

Routing to @getsentry/product-owners-dashboards for triage ⏲️

[hubertdeng123]

Removing Waiting for: Product Owner since issue seems to be assigned now